|Name||Fuel efficiency||Open flame interaction|
|Flammable||2||Becomes Ignited Gas and spreads|
|Highly flammable||3||Becomes Ignited Gas and spreads quickly|
|Explosive||4||Creates an explosion with power depending on gas volume|
|Highly explosive||5||Creates a powerful explosion with power depending on gas volume|
The fuel efficiency determines for how long a volume of gas can last as a fuel, or if it even counts as a fuel at all. For instance, a highly explosive gas can keep a furnace running for 5 times as long as a controllable gas, while a non-combustible gas will not work as fuel.